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Although anaerobic bacteria exist in abundance in cystic fibrosis (CF) airways, their role in disease progression is poorly understood. We hypothesized that the presence and relative abundance of the most prevalent, live, anaerobic bacteria in sputum of adults with CF were associated with adverse clinical outcomes. This is the first study to prospectively investigate viable anaerobic bacteria present in the sputum microbiota and their relationship with long-term outcomes in adults with CF. We performed 16S rRNA analysis using a viability quantitative PCR technique on sputum samples obtained from a prospective cohort of 70 adults with CF and collected clinical data over an 8 year follow-up period. We examined the associations of the ten most abundant obligate anaerobic bacteria present in the sputum with annual rate of FEV 1 change. The presence of Porphyromonas pasteri and Prevotella nanceiensis were associated with a greater annual rate of FEV 1 change; -52.3 ml yr -1 (95 % CI-87.7;-16.9), -67.9 ml yr -1 (95 % CI-115.6;-20.1), respectively. Similarly, the relative abundance of these live organisms were associated with a greater annual rate of FEV 1 decline of -3.7 ml yr -1 (95 % CI: -6.1 to -1.3, P =0.003) and -5.3 ml yr -1 (95 % CI: -8.7 to -1.9, P =0.002) for each log 2 increment of abundance, respectively. The presence and relative abundance of certain anaerobes in the sputum of adults with CF are associated with a greater rate of long-term lung function decline. The pathogenicity of anaerobic bacteria in the CF airways should be confirmed with further longitudinal prospective studies with a larger cohort of participants.

Aspirates from 48 chronically inflamed maxillary sinuses from patients who had nasal polyposis were processed for aerobic and anaerobic bacteria. Bacterial growth was present in 46 (96%) specimens. Aerobic or facultative bacteria were present in 6 (13%) specimens, anaerobic bacteria alone in 18 (39%), and mixed aerobic and anaerobic bacteria in 22 (48%). There were 110 bacterial isolates (2.4 per specimen). Thirty-nine of the isolates were aerobic or facultative organisms (0.85 per specimen). The predominant aerobic or facultative organisms were: Staphylococcus aureus, microaerophilic streptococci, Haemophilus influenzae and Moraxella catarrhalis. Seventy-one anaerobes were isolated (1.5 per specimen), Peptostreptococcus spp., Prevotella spp., Porphyromonas asaccharolytica and Fusobacterium spp. being predominant. These findings illustrate for the first time the presence of polymicrobial aerobic-anaerobic flora in patients with chronic maxillary sinusitis who had nasal polyposis.

Molecular methods have been used recently to investigate the bacteria encountered in human endodontic infections. The aim of the present study was to compare the ability of a 16S rDNA-based PCR assay and checkerboard DNA-DNA hybridisation in detecting Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Peptostreptococcus micros, Porphyromonas endodontalis, Por. gingivalis and Treponema denticola directly from clinical samples. Specimens were obtained from 50 cases of endodontic infections and the presence of the target species was investigated by whole genomic DNA probes and checkerboard DNA-DNA hybridisation or taxon-specific oligonucleotides with PCR assay. Prevalence of the target species was based on data obtained by each method. The sensitivity and specificity of each molecular method was compared with the data generated by the other method as the reference--a value of 1.0 representing total agreement with the chosen standard. The methods were also compared with regard to the prevalence values for each target species. Regardless of the detection method used, T. denticola, Por. gingivalis, Por. endodontalis and B. forsythus were the most prevalent species. If the checkerboard data for these four species were used as the reference, PCR detection sensitivities ranged from 0.53 to 1.0, and specificities from 0.5 to 0.88, depending on the target bacterial species. When PCR data for the same species were used as the reference, the detection sensitivities for the checkerboard method ranged from 0.17 to 0.73, and specificities from 0.75 to 1.0. Accuracy values ranged from 0.6 to 0.74. On the whole, matching results between the two molecular methods ranged from 60% to 97.5%, depending on the target species. The major discrepancies between the methods comprised a number of PCR-positive but checkerboard-negative results. Significantly higher prevalence figures for Por. endodontalis and T. denticola were observed after PCR assessment. There was no further significant difference between the methods with regard to detection of the other target species.

Repeated aspirations of sinus secretions by endoscopy was performed in five patients over a period of 34-50 days and, ultimately, surgical drainage was done in three who presented with acute maxillary sinusitis that did not respond to antimicrobial therapy and became chronic. The aspirates were cultured for aerobic and anaerobic bacteria. Most of the bacteria isolated from the first culture were aerobic or facultative bacteria: Streptococcus pneumoniae (three isolates), Haemophilus influenzae non-type-b (two) and Moraxella catarrhalis (one). Three of these cultures yielded bacteria that were resistant to the antimicrobial agents prescribed for treatment. Failure to respond to therapy was associated with the emergence of resistant aerobic and anaerobic bacteria in subsequent aspirates. These organisms included Fusobacterium nucleatum, pigmented Prevotella and Porphyromonas spp. and Peptostreptococcus spp. Eradication of the infection was achieved in all instances following the administration of antimicrobial agents effective against these bacteria, and in three instances by surgical drainage. This study illustrates the microbial dynamics of maxillary sinusitis that did not respond to antimicrobial therapy.

From 1974 to 1994, 504 isolates of Prevotella and Porphyromonas spp. were obtained from 435 (21%) of 2033 specimens from 418 children. They included 160 (32%) Pr. melaninogenica, 105 (21%) Pr. intermedia, 84 (17%) P. asaccharolytica, 58 (12%) Pr. orisbuccae, and 58 (12%) Pr. oralis. Most Prevotella and Porphyromonas spp. were isolated from abscesses (176), pulmonary infections (85), ear infections (82), wound infections (44), peritonitis (38), paronychia (15) and chronic sinusitis (14). Predisposing conditions were noted in 111 (27%) of the cases; these included previous surgery in 41 (10%), foreign body in 36 (9%), neurological deficiencies in 29 (7%), immunodeficiency in 21 (5%), steroid therapy in 12 (4%), diabetes in 8 (2%) and malignancy in 7 (2%). Prevotella and Porphyromonas spp. were the only isolates in 14 (3%) patients, and mixed infection was encountered in 404 (97%). The micro-organisms most commonly isolated with Prevotella and Porphyromonas spp. were anaerobic cocci (393 isolates), Fusobacterium spp. (108), Bacteroides spp. (B. fragilis group) (95), Escherichia coli (56) and other gram-negative anaerobic bacilli (52). Most Bacteroides spp. and E. coli were isolated from intra-abdominal infections and skin and soft tissue infections around the rectal area, whereas most Fusobacterium spp. were isolated from oropharyngeal, pulmonary and head and neck sites. beta-Lactamase production was detected in 191 (38%) Prevotella and Porphyromonas isolates from all body sites. All patients received antimicrobial therapy, and surgical drainage was performed in 173 (41%) cases. Four patients died from their infection. These data illustrate the spectrum and importance of Prevotella and Porphyromonas spp. in infections in children.